allen



Aug. 18, 1959 H. G. ALLEN FASTENER-APPLYING IMPLEMENT Filed June 4, 1951 4 Sheets Sheet 1 INVENTOR.

HOWARD G. 'ALLEN I yg m- ATTORNEYS Aug. 18, 1959 H. e. ALLEN FASTENER-APPLY'ING IMPLEMENT 4 Sheets-Sheet 2 Filed June 4, 1957 IN V EN TOR.

HOWARD G. ALLEN ATTORNEYS Aug. 18, .1959 H. s. ALLEN FASTENER-APPLYING IMPLEMENT 4 Sheets-Sheet 3 Fil ed June 4, 1957 INVENTOR. HOWARD G. ALLEN ATTORNE YS Aug. 18 1939 H. G. ALLEN FASTENER-APPLYING IMPLEMENT Filed Jun 4, 1957 4 Sheets-Sheet 4 ATTORNEYS United States Patent 2,899,679 FASTENER-APPLYING IMPLEMENT Howard G. Allen, Stoniugton, Conn., assignor to B- stitch, Inc., Stonington, Conn., a corporation of Rhode Island Application June 4, 1957, Serial No. 663,519

12 Claims. (Cl. 1- -'49) ing anvils are provided with sharpened points for penetrating the material of the work to position them for receiving the legs of a staple and clinching them in the material or on the under side of the flaps.

One object of the invention is to provide in a machine of the type indicated means for actuating the clinching elements or anvils to cause them to penetrate the material to the depth required and initially locking the anvils in operative relationship for receiving the ends of the legs of a staple as said staple is driven into the work.

Another. object is to provide means comprising a plunger for reciprocating the staple-driver of the machine and a crosshead reciprocable by said plunger for actuating the clinching elements before they 'are locked in operative relationship to clinch the legs of a staple as the driver continues to descend with the plunger for driving a staple into the work.

Another object is to provide in a machine of the type indicated a reciprocable plunger which may be operated either manually or by power with a staple-driver carried by and movable with said plunger, a crosshead initially connected to said plunger and carrying means for operating the clinching elements, and means for disconnecting said crosshead from the plunger and holding it in fixed position prior to the final action of the driver in driving the staple.

Another object of the invention is to provide manuallyoperable means for adjusting the stroke of the crosshead which actuates the clinching elements to regulate the extent of penetration of said elements into or through the material of the work.

Another object is to provide simple and convenient means comprising a hand-knob for adjusting the length of stroke of the crosshead in its descent with means for positively locking said adjusting means in fixed relationship.

Another object is to provide in a machine of the type indicated a reciprocating plunger, releasable means for connecting the crosshead to said plunger, said crosshead being reciprocated to actuate the clinching elements, and automatically-operated means for disconnecting the crosshead from said plunger and locking it in fixed position for regulating the desired extent of penetration of the clinching elements into the work.

Further objects of the invention are set forth in the following specification or will appear from an understanding thereof by those skilled in the art. The invention is herein descn'bed and illustrated, by way of example, as embodied in a preferred form of manually-operable machine, but it is to be understood that the construction and arrangementof its mechanism may take other forms 2,899,679 Patented Aug. 18, 1959 and be, adapted for purposes other than that herein indicated. In the accompanying drawings illustrative of a preferred embodiment of the invention:

Fig. l is a side elevational view of the complete machine with one side of the staple-magazine shown as partly broken away; v

Fig; 2 is a front 'view of the machine shown with certain parts broken away;

v Fig.3 is a part sectional view on line 33 of Fig. 1 looking in the direction indicated by the arrows;

Fig. 4 is an enlarged longitudinal sectional view of the fore part of the machine taken on line 44 of Fig. 2

and showing the operative elements of the mechanism with the staple-driver in raised position, and also illustra ting the manually-operable adjusting means for regulating the extent of penetration of the clinching anvils into the work;

Fig. 5 is a similar longitudinal sectional view of the machine showing the staple-driver at the end of its descent after driving a staple and illustrating the crosshead which actuates ithe clinching elements as locked in position at the endof its downward stroke; i

Fig. 6 is a composite view in perspective of one of the clinching elements including the arm or lever on which the: anvil is mounted for oscillation;

' Fig. 7 is an enlarged view of the operating mechanism of the machine including the reciprocable plunger, the staple-driver carried thereby, and the crosshead moved by the plunger'for actuating the clinching anvils, which latter are shown as withdrawn to' inoperative relationship;

Fig.8 is a similar enlarged view showing the parts at the end of the descent of the plunger and illustrating the clinching anvils as penetrated into anunder layer of material for clinching the legs of a staple in a blind stitch;

Fig. 9 is a view corresponding to Fig. 7 showing the clinching elements withdrawn from the work;

Fig. 10 is a vertical sectional view taken on line 10--10 of Fig. 9;

Fig. 11 is a view similar to Fig. 9 showing the clinching anvils as having been penetrated through three thicknesses of material and operated for clinching the legs of a staple within the lowermost layer; and

Fig. 12 is a vertical sectional view on line 12-12 of Fig; 11.

Machines of the present type are commonly used in the art for stapling together the flaps of closed cartons to seal such containers in condition for shipping. With many of the prior art devices, positive control of the clinching elements or anvils has not always been possible due to various causes. Moreover, where the movement of the staple-driver and the clinching anvils in continuous, that is without arrestment of the motion of the anvils, the work performed is not always satisfactory. It is therefore an object of the present invention to improve the mechanism and the method of operation of the device whereby the clinching anvilsare first brought to rest and locked in operative position before the staple .is .driven to engage the ends of its legs therewith.

It is a further object of the invention to provide convenient adjusting means for varying the length of stroke of the moving element which actuates the clinching anvils to insure a precise accurate control of the extent of penetration of the anvils into or through the work. Such accurate control is important for sealing cartons containing various products packed therein so that the legs of the staples will not penetrate clear through the'several overlying flaps of the carton to damage the goods contained therein; for example, by piercing can tops, engaging frangible or fragile parts of the packaged objects, or otherwise interfering with the contents of the carton. With the present improved construction 'control' of the penetration of the clinching anvils is positive and may be adjusted for different types of containers or other work wherein the legs of the staples must be prevented from projecting from the under side of one or more layers thereof.

In general, the present machine comprises an elongated staple-magazine 2 (Fig. 1) surmounted at its forward end by a vertical standard or housing 3 of triangular shape in front view (Figs. 2 and 3) which serves as a frame for mounting the operating elements of the machine. The main portion of the housing 3 is of hollow construction (Figs. 4, 7 and 8) comprising lateral Walls 4 and 5 and a rear wall 6 with a Vertical opening 7 at its center. Surmounting the top of the housing and integral therewith is a bifurcated bearing 8 between the sides of which an operating handle 10 may be pivoted on a crosspin 11. Projecting angularly from each side of the bearing member 8 are two horizontal hand-rests 12 which may be used for holding the implement down against the work.

Closing the front of the housing 3 is a hollow covermember 15 of complementary configuration having its side walls abutting the walls 4 and 5 of the housing and fastened thereto by screws 16 and 17 (Fig. 2). The forward wall of the cover 15 is slotted at 18 (Figs. 4, 5) to provide a guideway for receiving a slidable adjusting member or plate 70, later described.

The magazine 2 is of U-shape in cross-section as commonly used in the art and therefore it is not described in detail herein. The magazine 2 may be constructed of sheet-metal formed with a bottom wall 20 (Fig. 3) and upstanding side walls 21 terminating in inturned flanges 22 at the top. Extending longitudinally within the magazine 2 is a so-called core 25 formed of sheet-metal folded into U-shape with a bottom wall 26 and upstanding side walls 27 across which the staples s may be straddled, in a manner common to machines of the present type. A staple-pusher 30 (Fig. 1) shaped to slide on the core 25 is adapted to be drawn forwardly therealong by means of a helical spring 31 (Fig. 4) fastened thereto at one end, reaching forwardly therefrom to encircle a pulley 32 (Fig. 4) and thence extending rearwardly with its opposite end anchored to the side of the magazine 2, all as usually arranged. Projecting upwardly from the rearward end plate, is reduced in width laterally corresponding to that of the staple core 25 so that the staples may be supported with their legs depending at the sides of the plate to be fed forwardly thereacross for entering them into the staple throat 36 in which the staple-driver 40 reciprocates. The shear-plate 35 has laterally-projecting lugs 41 at the bottom extending outwardly to the sides of the magazine 2 and these preferably have beveled faces 42 inclined downwardly and forwardly to serve as camming means for forcing the lower ends of the legs of the staple in'timed relation to the operation of the staple-driver 40.

The staple-driver 40 may be in the form of a hardened metal blade welded or otherwise'suitably fastened tothe rearward face of the plunger 45. As shown in the present drawings, the driver-blade 40 is bifurcated at the top to 4 straddle the sides of the plunger 45 with the edges of the bifurcated portions 40' engaging in grooves 43 in the plunger. A hollow pin or rivet 44 extends through the blade 40 and plunger 45 for fastening these parts together.

The lateral edge portions of the driver-blade 40 slidably engage in slots 46 formed in ways 46 fastened to the rear wall 6 of the housing 3 by suitable means such as welding or screws (not herein shown) extending through the wall 6 from the rear. Extending rearwardly from the plun er 45 to project through the opening 7 at the center of the rear wall 6 of the housing 3 is a rectangular projection 48 (Figs. 1, 3, 10) which is slotted vertically on its sides to receive the edges of the bifurcations 40' of the driver-blade 40. The rearward end of the projection 48 is bifurcated to receive the end of a link 50 (Figs. 1, 4) for connecting the plunger to the operating lever or handle 10. The lower end of the link 51) is pivoted on a pin 51 and its upper end on a pin 52 extending between bifurcations 53 at the inner end of the handle 10. The forward face of the plunger 45 is formed with a transverse slot 54, the upper face of which is beveled or inclined at 55 at a slight angle to the horizontal (Figs. 5, 10 and 12) for a purpose later explained. At the bottom of the plunger 45 is a forwardly-extending lip or step 56 adapted to engage under a portion of a crosshead 57 for raising it as later explained.

The crosshead 57 is of substantially triangular shape in front view (Figs. 9-l1) and is releasably connected to the plunger 45 for actuating the clinching elements comprising the anvils 69 carried by levers or arms 61 (Fig. '6). Each clinching anvil 66 may be constructed from sheet-metal formed with a head-portion '62 and an arcuate or crescent-shaped extension 63 sharpened at its end for penetration into the work. The cresent-shaped portion 63 of the anvil 60 is formed adjacent its end with a concavity 64 for receiving the end of the leg of a staple to bend it into a clinch. The clinching anvils 60 are mounted at the outer ends of the arms 61 by means of screws 65 extending through their head-portions and threaded holes in the arms with cylindrical bearing bosses 66 engaged by the ends of the screws. The bosses 66 project from the opposite side of the arms 61' to serve for a purpose later explained. A pair of dowel-pins 67 hold each anvil 60 from turning on its screw 65. The inner end of each arm 61 is formed with a relatively large bore 68 for receiving a pivot-stud 69 projecting rearwardly from an adjustable plate-member '70 which is slidably mounted in the slotted recess 13, previously mentioned, on the inner face of the cover-member 15. The plate 7 0 is slidable vertically in the recess 18 for adjusting the position of the pivots 69. Thus, the axis of rotation for each arm 61 may be adjusted up or down to control the oscillating movement of the clinching anvils 6% so as to regulate the extent of their penetration into the work. As before indicated, the clinching elements, comprising the arms 61 and anvils 61 are oscillated from the reciprocating movement of the crosshead'57 by means of links 71 connecting the arms 61 thereto. Each link 71 is pivoted at its upper end on a stud 73 projecting forwardly from the outer, lower end of the crosshead 57 with the opposite end'of the link pivotally connected'to the boss 66, previously described, as fastened to the arm 61 by the screw 65.

The crosshead 57 is formed on its rearward side with rib-like runners 75 which overlap the sides of the plunger '45 to mount it for sliding movement relatively thereto.

The lower portion of the crosshead '57 is cut away at the center to form a rectangular opening 76 with a horizontal edge at its top engageable by the lip or step 56 on the plunger 57 for raising the crosshead after the clinching of a driven staple S. Above the opening 76 is a squareopening 77 in which is mounted a small cylinder or roller 80 adapted to engage in the transverse slot 54 in the forward side of theplunger 45 (Fig. :10) to 'r'elasably connect these two elements together for simultaneous reciprocation. During the initial downward movement of the plunger 45 the roller 80 rides on the face of the adjusting plate 70 to retain the roller in the recess or slot 54 in the plunger 45 for positive engagement with the lower edge of said recess. As the plunger 45 continues its descent, however, the beveled upper face 55 of the slot 54 will cam the roller 80 out of the slot 54 and into a transverse slot 82 in the rearward face of the plate 70 as shown in Figs. 5 and 12. The slot 82 in the plate 70 is similar in shape to the slot 54 in the plunger 45, being formed with a beveled upper face 83 which acts to force the roller back into the slot 54 as the plunger 45 reverses its motion and is moved upwardly to position the last-named slots in alinement. It will be understood from the foregoing description that the crosshead 57 is locked to the plunger 45 during the initial portion of the downward stroke of the latter, but is released therefrom before the plunger reaches the end of its descent. Then as the plunger rises, the crosshead 57 will again be connected thereto in a manner more fully explained in connection with the operation of the complete machine.

The plate 7 0 is manually adjustable vertically for raisiing or lowering the pivot-studs 69 to regulate the extent .of oscillating movement of the clinching anvils 60 by 311163118 of a hand-knob 85 (Fig. 4).

The hand-knob :85 is rotatively connected with a shaft or spindle 86 jour- -.naled in a bearing boss 87 projecting forwardly from the t-cover-section of the housing 3. The knob 85 is ;formed with longitudinal slots 88 in its hub 89 engaged 'rby the ends of a pin 90 in the shaft 86 for keying the llknob rotatively with the shaft. Inserted into the inner end of the shaft 86 is a hollow crank-pin 91 disposed eccentrically of its axis. The pin 91 engages a hole in a square block-like member or slide 92 which is fitted to a transverse slot 93 in the plate 70 whereby to cause it to raise or lower the plate when the crank-pin is turned by the shaft 86.

A series of shorter slots or radial notches 95 in the end of the hub 89 of the knob 85 are provided for locking the knob and thereby the shaft 86 in any one of several adjusted positions. A pin 96 projecting from the end of the bearing boss 87 is engageable with one of the slots 95 to lock the shaft 86 against rotation after the knob 85 has been turned for adjusting the plate 70. A collar 97 fastened to the outer end of the shaft 86 by means of a spring-ring 98 is received in .a counterbore 99 in the end of the knob 85. A helical spring 100 surrounding the shaft 86 within a second counterbore 101 bears against the end thereof with its opposite end engaging the collar 97, thereby tending to hold the knob 85 with one of its slots 95 engaged with the locking pin 96. The knob 85 may be drawn outwardly against the tension of the spring 108 to release the selected slot 95 from the locking pin 96 to allow the knob to be turned. A collar 105 fastened to the inner end of the shaft 86 by a spring ring 166 engages the end of a counterbore .107 in the cover 15 to prevent the shaft from being withdrawn from the bearing boss 87.

Releasable detent-means are provided for retaining the lever or handle 10 in raised relationship after it has been rocked upwardly. Referring to Figs. 2 and 4, the pivoted end of the handle 10 has a pair of sheetmetal members 110 located between its two bifurcated portions and provided with circular cam-members 111 at their forward ends. The members 110 extend rearwardly and surround the cross-pin 52 to adapt them to pivot thereon with the motion of the handle 10. Each member 110 is cut away along its edge to form an inclined earn-face 112 engaged by the beveled end of a hollow sleeve 113. The sleeve 113 is slidably mounted .in a vertical bore 114 in the upper bearing portion 8 on the housing 3. A helical spring 115 contained in the sleeve 113 bears at its lower end against a centrallyrecessed pin 116 inserted in a transverse bore 117 in the bearing. The spring 115 thus tends to force the sleeve 113 upwardly to engage its beveled end with the camface 112 on the members 110 to retain the handle 10 in raised relationship. When, however, the handle 10 is manually depressed the spring 115 allows the plunger sleeve 113 to yield so that the cam-faces 112 on the member 110 are disengaged from its end. If desired, however, a spring may be applied for returning the handle to raised relationship after each operative stroke as usually arranged.

Before starting the operation of the machine the plate may be adjusted for varying the position of the pivots 69 of the anvils 60 to control the extent of their penetration into the work. The adjusting plate 70 may be raised or lowered as necessary by turning the hand-knob to rotate the shaft and cause its crank-pin 91 to shift the slide 92 for sliding the plate vertically. It has been explained that the knob 85 may be turned by drawing it outwardly on the shaft 86 to release its particular slot from the pin 96. After the adjustment has been completed the spring will slide the knob 85 back into place and engage its selected notch 95 with the pin 96 for locking the shaft 86 from turning so as to secure the plate 70 in adjusted position. The notches 95' may be marked with indicia to facilitate adjusting the pivots for the clinching anvils 60 in the desired relationship.

The complete implement or machine is operated in the manner as next explained. With the handle 10 held in raised position by the detent-means, last above described, the operator presses it downwardly to cause the plunger 45, connected thereto by the links 50 to descend through an operating stroke. During the initial downward motion of the plunger 45, the crosshead 57 is connected thereto by means of the roller 80 engaging in its slot 54 (Fig. 4). The crosshead 57 will thus descend with the plunger 45 and through its connection by the links 71 to the arms or levers 61 the levers will be rocked to oscillate the clinching anvils 60 for penetrating them into the material of the work; such as the overlying flaps f and of a carton blank B (Fig. 8).

At this juncture the movement of the clinching elements is arrested by disconnecting the crosshead 57 from the plunger 45 so as to retain the anvils 60 in proper relationship for receiving the legs of the staple as the driver 40 continues its descent with the plunger. For example, Fig. 8 illustrates the clinching anvils as inserted through the upper flap f and into an underlying flap 1" without emerging therebelow; while Fig. 11 shows the staple-clinching means as arranged for clinching a staple having longer legs for penetrating the material of a third layer of material in the flap f without protruding from the under side thereof. However, in this instance the ends of the clinching anvils 60 may penetrate through this third layer to a slight extent providing the material contained in the carton is such that it will not be damaged by contact of the anvils therewith.

The disconnection of the crosshead 57 from the plunger 45 is accomplished by releasing the roller 80 from the slot 54 in the plunger. This occurs when the opening 77 in the crosshead 57 reaches a point in register with the slot 82 in the adjusting plate 70 (Fig. 12). At this juncture the inclined cam-face 55 in the slot 54 acts to cam the roller 80 laterally out of the slot .54, through the opening 77 and into the slot 82 of the plate 70 so that the crosshead is restrained from further downward movement as the plunger 45 continues its descent with the roller riding on the forward face of the plunger. During this latter descent of the plunger 45 the staple-driver 40 is moved downwardly thereby to drive a staple S down in the throat 36 to penetrate its legs s into the work until the ends thereof engage in the depressions or recesses 64 in the arms 63 of the anvils 60. Further downward movement of the driver 40 will consequently cause the ends of the legs to be bent or curled upwardly as shown,

in Figs. 8 and 11 to clinch them for securely holding the several flaps fot the carton bound together for sealing the closure.

After each staple has been driven into the work and clinched 'in the material thereof the operating lever or handle is swung upwardly to Withdraw the plunger 45 and restore the crosshead 57 'to initial relationship as shown in Figs. 4 and 10. As the plunger 45 is raised by upward movement of the handle 10 its lip or step 56 will eventually come -into engagement with the upper edge of the bottom opening '76 in the crosshead 57 to initiate the raising or the crosshead. During the initial upward movement of the .plunger its slot 54 will register with the slot 77 in the crosshead 57 and cause the beveled cam-face 83 in the slot 82 of the plate id to force the roller 30 through the opening '77 and into the 'slot 54 to reconnect the two elements to descend together (Figs. 1, 4 and 10) for the next operative stroke. The parts are thus restored to initial relationship to provide tor a repeat operation of driving and clinching another staple in the work.

It will be observed from the foregoing description that the present invention provides an improved imple ment or machine for driving staples through several layers of material and clinching their legs therein without penetration therethrough. A particular feature of the improvement consists in the provision of adjusting means for regulating the extent of penetration of the clinching anvils into the work and thereby the location of the clinched legs of a staple. The adjusting means is convenient to operate and readily accessible from the outside of the machine without disassembling or disconnecting any of the Working parts of the mechanism to change their location or relationship.

While the improved machine is herein illustrated and described as embodied in one preferred form of construction by way of example, it is to be understood that modifications may be made in the structure and arrangement of the parts of the device without departing from thereby, a crosshead, means for releasably connecting said crosshead to said'plunger for movement therewith, an adjustable member, clinching anvils pivoted to said adjustable member to adapt them to oscillate relatively thereto, means connecting said crosshead to oscillate the anvils to cause them to penetrate the work in position to engage the legs of a staple to clinch them, and means -for adjusting said adjustable member for locating the pivots of said anvils at different distances from the pivotal 'axis of said lever to regulate the extent of penetration of the anvils into the work.

2. Ina machine of the type indicated having a casing adapted to rest on the work, an operating lever pivoted to a stationary part of said'casing to adapt it to rock about a fixed axis, a reciprocable plunger in said casing, staple-driving means reciprocable by said plunger, clinching anvils having sharpened ends adapted to penetrate the work in position to receive and clinch the legs or" a driven staple, an adjustablemember, means for mounting said adjustable member to move toward and away from thefixed axis of said operating lever, means for pivotally mounting said clinching anvils on said adjustable member to adapt them to oscillate for penetrating their sharpened ends into the work, a crosshead reciprocable by said plunger, means for connecting said crosshead to oscillate said-clinching anvils, means for arresting the movement of the crosshead after the anvils have been moved into position for clinching the legs of a staple, and manually-operable means accessible from the outside of the machine for adjusting said adjustable member to locate the pivots of said anvils at dilferent distances from the pivotal axis of said operating lever so as to varythe extent of penetration of said anvils into the work.

3. In a stapling machine, a housing, a plunger reciprocable in said housing, a crosshead releasably connected to said plunger to reciprocate therewith, an adjusting member slidablymounted in said housing, a pair of clinching anvils pivotally mounted on said adjusting member to adapt them to oscillate relatively thereto, means connecting said crosshead to said anvils for oscillating them to cause their ends to penetrate into the work, said operating lever pivotally mounted on a stationary part of said housing independently of said adjusting member, eccentric means for sliding said adjusting member, and manually-operable means on the outside of the housing for actuating said eccentric means to raise or lower said adjusting member.

4. In a machine of the type indicated, a reciprocable plunger, a fastener-driver reciprocated by said plunger, :1 pair of pivoted anvils for clinching the legs of fasteners as they are driven into the work, a crosshead connected to said anvils for oscillating them to penetrate them into the work, means for releasably connecting said crosshead to said plunger, means for releasing said crosshead from the plunger prior to driving a fastener into the work, a projection on said plunger engageable under said crosshead for raising the latter as the plunger is raised after the driving and clinching of a fastener, and means for reconnecting said crosshead to said plunger as the latter is returned to initial relationship after driving and clinching a fastener.

5. In a stapling machine of the type indicated, a stapledriver, a plunger for reciprocating said driver, a crosshead releasably connected to said plunger, a pair of pivoted clinching anvils connected to said crosshead for oscillation thereby to penetrate them into the work, means for disconnecting said crosshead from said plunger after said anvils have been brought into operative position for clinching the legs of a staple, means on said plunger positively engageable with said crosshead for raising it during the return stroke of said plunger, and means to releasably reconnect said crosshead to said plunger as the plunger returns to initial position for repeating the operation of driving and clinching another staple.

6. In a machine of the type indicated comprising a reciprocable plunger and a staple-driver reciprocable by said plunger, a crosshead, clinching anvils, means connecting said crosshead to said clinching anvils for moving them into operative relationship, a shiftable member carried by said crosshead, a recess in said plunger engageable by said shiftable member to connect said crosshead therewith, a manually-adjustable member, means on said adjustable member for engaging saidconnecting member to release said crosshead from said plunger, means on said plunger engageable with said crosshead for raising it after the driving and clinching of a staple, and means on said adjustable member for shifting said shiftable member to reconnect said crosshead to said plunger as the plunger reverses its stroke to return to initial position.

7. In a stapling machine comprising a casing adapted to rest against the work, an operating lever pivoted to a stationary part of said casing, a plunger reciprocable by said lever, a staple-driver reciprocable by said plunger with a constant length of stroke, a crosshead connected to said plunger for reciprocation thereby, an adjusting member slidable vertically within said casing, a pair of retractible cl'mching anvils having pointed ends for penetrating the work, means pivotally mounting said anvils on said adjusting member for rocking about their pivots, means connecting said crosshead to said clinching anvils for rocking them to penetrate their" ends into the work,

means for arresting the movement of the crosshead to maintain the anvils in fixed relationship after they have been moved into operative relationship for clinching the legs of a staple, and manually-operable means for raising and lowering said adjusting member to displace the pivots of the clinching anvils toward and away from the pivotal axis of said operating lever to vary the extent of penetration of said anvils into the work.

8. In a machine for stapling the flaps of cartons, a frame adapted to rest against the flaps, an operating lever pivoted directly to a stationary part of said frame, a plunger slidable on said frame, a link connecting said operating lever to said plunger for reciprocating it, an adjusting member slidable on said frame, a pair of clinching anvils pivotally mounted on said adjusting member to oscillate for penetrating their ends into the work, a crosshead reciprocable on said frame, means releasably connecting said plunger to said crosshead for reciprocating it, links connecting said crosshead to said clinching anvils for oscillating them, means for disconnecting said crosshead from said plunger after the anvils have penetrated into the work, eccentric means for sliding said adjusting member to raise and lower the pivots of the clinching anvils toward and away from the pivotal axis of said operating lever, and manually-operable means on the outside of said frame for turning said eccentric means to raise and lower said adjusting member.

9. In a machine of the type indicated comprising a casing, an operating lever pivoted to a stationary part of said casing to rock about a fixed axis with a constant length of stroke, a plunger slidably mounted within said casing, a fastener-driver reciprocated by said plunger, an adjustable member slidable within said casing, a pair of anvils pivotally mounted on said adjusting member to adapt them to rock for penetrating the work and clinching the legs of the fastener driven therethrough, a crosshead connected to said anvils for oscillating them, means for releasably connecting said crosshead to said plunger, means for releasing said crosshead from said plunger prior to driving a fastener into the work, means engageable between the plunger and crosshead for raising the latter after the driving and clinching of a fastener, means for reconnecting said crosshead to said plunger as the latter is returned to initial relationship after driving and clinching a fastener, eccentric means for raising and lowering said adjusting member toward and away from the pivot of said operating lever, and means on the outside frame for operating said eccentric means.

10. In a stapling machine comprising a casing, an operating lever pivoted directly to a stationary part of said casing to swing about a fixed axis, a plunger reciprocable within said casing, staple driving means reciprocable by said plunger, an adjusting member slidable vertically within said casing, retractible anvils pivoted on said adjusting member for oscillation to penetrate the work in position to clinch the legs of a driven staple, pivots on said adjustable member for rockably mounting said clinching anvils, means for connecting said plunger to said anvils for oscillating them, an eccentric disk in said casing engaging said adjusting member for raising and lowering it to displace the pivots of the clinching anvils toward and away from the pivotal axis of said operating lever, a shaft journaled in said casing for rotation to turn said eccentric disk, and a hand-knob on the outside of said casing connected to said shaft for turning said eccentric disk to adjust the adjusting member vertically relatively to the pivotal axis of said operating lever.

11. In a machine of the type indicated comprising a casing, an operating lever pivoted to a stationary part of said casing to rock about a fixed axis, a plunger slidable within said casing, means connecting said operating lever to said plunger for reciprocating it, a reciprocable crosshead, means for releasably connecting said plunger to said crosshead for reciprocating it, an adjustable member slidable within said casing, pivots on said adjustable member, a pair of clinching anvils rockably mounted on said pivots, means connecting said crosshead to said anvils for rocking them, means for releasing said crosshead from said plunger after the anvils have been rocked to penetrate the Work, eccentric means engaging said adjustable member within said casing, a shaft connected to said eccentric means, a hand-knob carried by said shaft on the outside of said casing for operating said eccentric means to raise and lower said adjustable member for locating the pivots of said anvils at different distances from the pivotal axis of said operating lever, and means for locking said knob from turning to maintain said adjustable member in adjusted position relative to the pivotal axis of said operating lever.

12. In a stapling machine, a casing, a plunger reciprocable in said casing, a staple-driver connected to said plunger for reciprocation thereby, a lever pivoted on a stationary part of said casing, means connecting said lever for reciprocating said plunger, a crosshead, means for releasably connecting said crosshead to said plunger, an adjustable member slidably mounted on said casing, clinching anvils pivoted to said adjustable member, means connecting said crosshead for oscillating said anvils to cause them to penetrate the work, eccentric means engaging said adjustable member, a shaft journaled in said casing and connected to said eccentric means for operating it to raise and lower said adjustable member for locating the pivots of said anvils at different distances from the pivotal axis of said lever, and means outside the casing for manually rotating said shaft to operate said eccentric means.

References Cited in the file of this patent UNITED STATES PATENTS 2,469,055 Schafroth May 3, 1949 2,722,001 Schafroth Nov. 1, 1955 2,722,002 Allen NOV. 1, 1955 

